dahlhaus etal



Jan. 24, 1956 DAHLHAUS ET AL 2,732,530

MOUNTINGS FOR TUBULAR ELECTRIC DISCHARGE LAMPS, SUCH AS FLUORESCENT LAMPS,OR FLUORESCENT TUBES Filed Sept. 25, 1952 5 Sheets-Sheet 1 I .J 2 Q 24 \A 7/ Z5 11 Inventors Hex HAN/V flA/IL AM 0 Jan. 24, 1956 H. DAHLHAUS ET AL 2,732,530

MOUNTINGS FOR TUBULAR ELECTRIC DISCHARGE LAMPS, SUCH AS FLUORESCENT LAMPS,OR FLUORESCENT TUBES Filed Sept. 25, 1952 5 Sheets-Sheet 2 Fig.2

3 l I E 3 Age/er Mil 76771901 b m 5 ATT'G RNEY Jan. 24, 1956 DAHLHAUS ET AL 2,732,530

MOUNTINGS FOR TUBULAR ELECTRIC DISCHARGE LAMPS, SUCH AS FLUORESCENT LAMPS,OR FLUORESCENT TUBES Filed Sept. 25, 1952 5 Sheets-Sheet 3 Fly. 4

22 2 31 8 40 II a 5 l -i l 25 25 24 24 Inventor's HERMAN flAHL-l/A 1/5 A frame 7 2,732,530 S, SUCH 5 Sheets-Sheet 4 1 wad H. DAHLHAUS ET LAR ELECTRIC DISCHARGE LAMPS l E} l u Jun-L m o i -1- ANN 2 m 5 AS FLUORESCENT LAMPS,OR FLUORESCENT TUBE Jan. 24, 1956 MOUNTINGS FOR TUBU Filed Sept. 25, 1952 Jan. 24, 1956 H. DAHLHAUS ET L 2,732,530

MOUNTINGS FOR TUBULAR ELECTRIC DISCHARGE LAMPS. SUCH As FLUORESCENT LAMPS,OR FLUORESCENT TUBES Filed Sept. 25, 1952 5 Sheets-Sheet 5 Fig- 0 Inventor? Xlzesnr 4602mm? by W S.

Arr-a R Y United States Patent MOUNTINGS FOR TUBULAR ELECTRIC DIS- CHARGE LAMPS, SUCH AS FLUORESCENT LAMPS, 0R FLUORESCENT TUBES Hermann Dahlhaus, Ludenscheid, Westphalia, and Albert Winterhotf, Leifringhausen, Westphalia, Germany, assignors to Vossloh-Werke G. m. b. 1-1., Werdohi, Westphalia, Germany, a limited corporation of Germany Application September 25, 1952, Serial No. 311,456 Claims priority, application Germany December 6, 1951 7 Claims. (Cl. 339-52) This invention concerns mounting fittings for use in the installation of tubular electric discharge lamps, such as fluorescent lamps or fluorescent tubes, and especially to fittings for lighting strips which are arranged in the open air, or in damp rooms. The invention is applicable to mountings for fluorescent lamps arranged end to end longitudinally, and also to lighting groups consisting of individual lamps.

Such fittings, if they are to conform satisfactorily to practical requirements, must not only ensure a satisfactory sealing of the live conducting parts from the weather, but must also render possible a convenient and simple assembly and also an easy interchanging or renewal of parts subjected to wear and tear, such as lamps, starters and the like. In addition, the fittings should have a pleasing appearance.

The mountings or fittings constructed in accordance with the present invention satisfy these requirements to a great extent. Above all, they ofier the advantage of a particularly easy electrical installation, which allows the connection of all circuits, for example, of a lighting strip of any desired length, to be carried out in the simplest manner.

These fittings consist chiefly, in a known manner of terminal lamp holders for the ends of a lighting strip and intermediate lamp holders between end-to-end lamps in a lighting strip.

The mounting fittings according to this invention comprise detachably connected upper and lower parts, the upper part including contacts and holding means for the lamp tube (or tubes) and the lower part being adapted for independent fixture on a support and including all terminals necessary for complete inclusion of the mounting in an installation, said upper and lower parts having mutually-engaging contacts, separable by the separation of those parts, whereby the lamp tube or tubes may be brought into circuit with the installation as the parts are brought together and' out of circuit as the parts are separated.

The contact devices for the'pin socket of the lamps include means, in known manner, to compensate for differences in the length of the lamps.

The assembly and the electric installation of lighting strips and/or lighting groups consisting of fluorescent lamps is considerably facilitated and made cheaper by this invention, because all lamp holder lower parts, and all switch gear of a lighting strip or a lighting group can be mounted independently of the lamp tubes, which tubes can then be readily placed in position. Advantageously, a four-conductor cable is used which is led continuously commencing from the terminal lamp holder at the beginning of the lighting strip through all intermediate lamp holders and switch gears to the other end of the lighting strip. At the terminal blocks in the lamp holders the conductors of the cable are separated, stripped and connected to the connecting terminals. it is also possible to use short cable sections which each lead from lamp holder to lamp holder and/or lamp 2,732,530 Patented Jan. 24, 1956 holder to switch gear. When the installation of the lower parts is completed, the upper parts of the lamp holders are slipped on and screwed on. After insertion of the lamps the installation is ready for operation.

In the known fittings, some of which are already provided with lamp holder casings separable into upper and lower parts, this simple manner of electric installation is impossible. The connecting terminals for the lamp circuit is situated in the upper part of the lamp holder, so that thecable must be connected to a removable part.

Further features and advantages of the invention are explained in the following description, referring to the accompanying drawing which shows one example of the invention. The drawing shows a waterproof fitting particularly suitable for fluorescent lamps for the installation of lighting strips.

Fig. 1 shows a terminal lamp holder, with incorporated starter, in longitudinal section;

Fig. 2 is a cross section through the lamp holder according to Fig. l in the plane of the connecting screws of the upper and lower parts;

Fig. 3 shows the plan view of the lower part of the lamp holder according to Fig. 1;

Fig. 4 shows an intermediate lamp holder in longitudinal section through the centre;

Fig. 5 is a plan view of the lower part of this lamp holder;

Fig. 6 shows, on a reduced scale, a lighting strip comprising two fluorescent lamps;

Fig. 7 is the circuit diagram of a lighting strip comprising fluorescent lamps arranged end to end;

Fig. 8 is the circuit diagram of a lighting group comprising two individual fluorescent lamps;

Fig. 9 shows an individual item on an enlarged scale; and

Fig. 10 shows a terminal lamp holder in side elevation.

As shown more particularly in Figs. 1-3, a terminal lamp holder of waterproof and gasproof construction consists of a cap-like upper part 1 to which is joined the lower part 2 by means of the screws 3, there being a packing element 4 between them. These upper and lower parts are preferably moulded from synthetic insulating material.

Removably housed in the upper part 1 is the contact device 5 for the complemental contact 6 of the fluorescent lamp, and said part 1 also houses the starter 7 with its contact device 8. It is preferable that the contact device 5 for the fluorescent lamp be connected with the contact device 8 of the starter 7, in the form of a prefabricated unit in which the electric connections have already been established in an expedient manner. For the easy replacement of the starter there is provided an easilyaccessible screw cap Q, under which is a suitable packing or sealing element and which may consist of transparent synthetic material so as to make the observation of faults more easy, say when the starter ceases to function.

This of course would presuppose that the starter housing underneath the cap is provided with a window not shown but known in the art, through which the glowing of the starter is visible.

For the purpose of sealing the lamp shell 10 there is provided, in accordance with the invention, a sealing sleeve 11 of resilient material, e. g. rubber, synthetic rubber or the like, the sleeve being of stepped form and with its two marginal edges strengthened by annular enlargements 12 and 13. The one marginal edge 12 of the said sealing sleeve 11 is clamped on to the upper part 1 by means of a ring 14 provided at its one end with an inner screw thread which screws on to the externally threaded rim of an opening in the upper part 1. The other thickened marginal edge 13 acts as sealing edge and is pressed against the lamp shell by a clamping ring 15 having an axially-displaceable inclined annular surface 17, and being screwed on the other end of the ring 14 which is provided with an outer screw thread of a hand opposite to that of the mentioned inner thread of the ring 14.

The inclined annular surface is preferably formed, -as shown, by a metal thrust collar or ring 17, which, by means of the shoulder 16 on the clamping ring 15, is moved axially towards the lamp shell and thus presses the sealing edge 13 of the resilient ring 11 against the lamp shell. The thrust surface of the thrust collar 17 is preferably provided with concentric, channel-like grooves 18 (see Fig. 9) which result in an improved thrust effect. For guiding the thrust collar 17 in an axial direction and for limiting its axial movement there are provided guide projections 19 which have their widened ends 2! engaged in corresponding depressions 21 in the screw ring 14 (see Fig. 4)

For stitfening the clamped marginal edge 12 of the sealing sleeve 11 a thin-walled metal ring 22 is inserted into the open end of the ring 11, and this may also be firmly connected to the sealing sleeve 11, e. g. by being vnlcanised therein. This metal ring 22 should ensure that the axial tensile stress occasioned by the pressing of the sealing edge 13 outwards to the lamp, does not drag the clamped marginal edge 12 from its proper position.

In order to facilitate the unscrewing of the screwed ring 14, arrangement may be made, as shown more clearly in Fig. 10, by which the screwed ring 14 and also the clamping ring 15 are provided on their opposed annular faces with projections 14 and 15 respectively. If the clamping ring 15 is screwed back, i. e. away from the lamp, the projections 14 and 15 eventually abut against one another and form a coupling, effective only in one direction of rotation, by which on continued rotation of the clamping ring 15, the detachment of the screwed ring 14 is effected, because the screwed ring 14 has a thread of opposite hand to that of the clamping ring 15. At the same time, this coupling prevents the two rings 14, 15 from jamming one on the other because, the coupling 14 15 becomes effective before the clamping ring 15 has reached the inner end of the threaded portion of the ring 14.

The lower part 2 which is adapted to be mounted on Walls, ceilings and the like by means of its base plate 23 (in the drawings it is shown as it would rest on a support) is provided with known stuifing boX screw connections or unions 24 for the purpose of the water-tight and gas-tight connection of the feed cable or conduits therefor. However, it may, alternatively, be provided merely with threaded sockets into which conduit tubing may be screwed.

The hollow space 26 of the lower part 2 is bridged by a terminal block 28 fitted with a series of terminals, which block is held in a corresponding recess 29 in the part 2 and is secured to that part by screws 28a. The terminals of block 28 are in conductive connection with the contact devices of the starter 7 situated in the upper part 1, and with the contact for the lamp. This connection is so arranged, in accordance with the invention, that when detaching the upper part 1 from the lower part 2, it is automatically separable. For this purpose, the two outer connecting terminals 27 (Figs. 2 and 3) are provided with strip-like contact blades 30 which, when the lamp holder casing 1, 2 is assembled, are inserted into corresponding sheaths which are formed by spring contacts 31 connected to the contact devices 5 and 8. For guiding the contact blades 3% in the upper part 1, grooved projections 32 are provided in the upper part, whilst other projections 33 act as supports for the spring contacts 31, to take the thrust. Thus, the two outer terminals 27 serve for the connections of the lamp circuit,

whilst the two inner terminals 27 are provided for the lead-ins.

For the mutual electric screening of the outer and inner terminals there are provided between the two outer terminals 27 and the inner connecting terminals 27 (and preferably also between the inner connecting terminals themselves) spacing lugs 34, which are integrally constructed with the terminal block 28.

With a suitable construction of the lower part 2, it is easy to incorporate in the hollow space 26, the chokes or the like which are usually accommodated in the socalled switch gears. The overall effect of the lamp fitting is thereby considerably enhanced, the switch gears not spoiling the appearance as they have done hitherto.

In the lighting strip comprised of two fluorescent lamps arranged end to end and shown in Fig. 6, the left hand terminal lamp holder 35 corresponds to the one described above with reference to Figs. l-3. The right hand terminal lamp holder 36 has a similar casing, similar sealing means for the lamp shell and a similar terminal block. However, it contains an axially-displaceable contact device, of known construction, by which differences in the length of the lamps may be compensated. Further, this lamp holder 36 is not equipped with a starter because only one starter (that in lamp holder 35) is necessary in the single lamp circuit. The two terminal lamp holders 35 and 36 make a pair of lamp holders which, in connection with the necessary switch gear, may easily be used for installing an individual fluorescent lamp extending from the one to the other.

The intermediate lamp holder 37 receives the pin sockets of the adjacent ends of two end-to-end fluorescent lamps. in principle, it is constructed in the same manner as the terminal lamp holders 35, 36. Its upper part 38 (Fig. 4), however, has two casing openings, one in each of two opposite sides, which are provided with similar sealing devices 11 to 17 for the lamp shell as are used in the terminal lamp holders. Besides containing a complete contact device as used in the left hand terminal lamp holder 35, it also contains an axially displaceablc contact device as used in the right hand terminal lamp holder 36. The screw cap 9 provided for the changing of the starter 7 corresponds to the one shown in Figs. 1 and 2.

It is obvious that the use of a large number of completely similar constructional parts is of considerable economic advantage. In correspondence with the con tact devices combined in one lamp holder casing, the terminal block 42 in the lower part 39 of the intermediate lamp holder, has outwardly disposed pairs of connecting terminals 46 and 41, each of which pairs is intended for one lamp circuit. Correspondingly, there are also two pairs of contact blades 30 and spring contacts 31, in order to establish the conductive connection between the pairs of terminals 40, 41 and the contact devices in the upper part 38.

The advantages of an electric installation provided by the present invention are apparent from a consideration of two examples of circuit diagram shown in Figs. 7 and 8. First, the wiring diagram in Fig. 7 is for a lighting strip having three end-to-end lamps. The installation is carried out by means of a four-conductor cable which passes through the successive fittings from one terminal lamp holder to the other, or by cable sections passing from fitting to fitting. Two conductors 43 of the cable lead to the supply current, which is conducted to each of the pairs of terminals 44 of the switch gears 45. These supply terminals 44 are connected with the choke-equipped inputs of the lamp circuits. One serves as a conductive connection for the terminals 40 or 41 of the intermediate lamp holders 37, and the other is an output terminal for the choke. Sections of the third conductor 48 of the cable connect individually the output terminals 46, 47 of the chokes with one of the terminals of the terminal pair 27 or 49, 41 in the lamp holders. Moreover a section of the fourth conductor 49 of the cable is associated with each tubular lamp and these sections 49 form the feeds for the glow starters in the lamp holders of the respective tubular lamps. For each of these feeds a separate terminal 50 is provided in the switch gears 45.

When using a continuous cable its conductors are separated at the actual terminal points, stripped, and connected to the terminals. When using cable sections which extend only from a lamp holder to the switch gear, the supply current must be fed continuously through the entire lighting strip to the center terminals 27 of each lamp holder. As the connecting terminals on the terminal blocks 28 and 42 of the lamp holders as well as of the switch gears are situated close to one another, the installation suffers only minor losses in wire (wiring material).

Fig. 8 shows the wiring diagram, similar in principle to that in Fig. 7, of a lighting group consisting of individual lamps each between terminal fittings. In this case also, important advantages result in the installation.

What We claim is:

l. A mounting for a tubular electric discharge lamp, comprising a base part having means to eitect a waterand gas-tight connection of a feed cable thereto, a terminal block seated in said base part, said block including a plurality of terminals and conductive members projecting from selected ones of the terminals, an upper part detachably and sealingly connected to the base part, contact elements carried by said upper part and adapted for automatic engagement with and disengagement from said members responsive to connection and disconnection, respectively, of the upper and base parts, one of said elements being arranged for engagement with a complemental contact of an electric discharge lamp, a sealing sleeve carried by said upper part and including reinforced end flanges, one of said end flanges being circumposed about and being clampingly engaged with the lamp-engaging contact element of the upper part, the other end flange being formed as a sealing rim circumposed about the lamp, and a flared clamping ring circumposed about said rim and mounted on the upper part for axial displacement into engagement with the rim, to radially contract the same into sealing engagement with the lamp.

2. A lamp mounting as in claim 1, wherein said terminal block is formed separately from the base part, said base part having a cavity and said block bridging said cavity, the base part having recesses formed in opposite walls thereof to receive opposite ends of the terminal block.

3. A lamp mounting as in claim 2, and wherein said cavity is shaped to receive the switch gear of an electric discharge lamp assembly.

4. A lamp mounting as in claim 1, said conductive members being formed as strips, the contact elements of the upper part engageable thereby being provided with sheaths slidably engaging said strips.

5. A lamp mounting as in claim 1, said clamping ring having guide projections formed thereon, the upper part having depressions receiving said projections to limit axial movement of the ring, said mounting further including a ring element mounted on the upper part adjacent said ring for threaded advancement thereagainst to axially shift the same against the sealing rim.

6. A lamp mounting as in claim 1, and said clamping ring having a series of concentric, annular grooves formed on the rim-engaging surface thereof for gripping of the sealing rim during the radial contraction thereof.

7. A lamp mounting as in claim 5, and further including a second ring element threaded onto the upper part, the first named ring element being threaded upon the second-named element, said second ring element being engageable against said one end flange to clamp the same to the lamp-engaging contact element, the first and second ring elements having confronting abutments interengaging on threading of the ring elements toward one another, to link the ring elements as a coupling active in only one direction of rotation when the ring elements approach one another.

References Cited in the file of this patent UNITED STATES PATENTS 1,878,229 Beck Sept. 20, 1932 2,109,341 Rebl Feb. 22, 1938 2,401,555 De Reamer June 4, 1946 2,507,898 Gaynor et al. May 16, 1950 FOREIGN PATENTS 140,339 Switzerland Aug. 16, 1930 584,720 Great Britain I an. 21, 1947 

